Annealing cover or the like



June 13, 1939.

e. M. CROFT ANNEALING COVER OR THE LIKE Filed Sept. 28, 1958 INVENTOR George A4, Cmff Patented June 13, 1939 UNITED STATES PATIENT OFFICE ANNEALING CQVER OR THE LIKE Application September 28, 1938, Serial No. 232,118

2 Claims This invention relates, to annealing covers or similar open-bottomed box-like metal structures. Various types of annealing covers have been I tried heretofore but none of them, so far as I am 5 aware, has provided a satisfactory solution to the problem presented by the warping, sagging and distortion of metal walls under the extreme temperatures at which annealing covers must operate. Attempts have been made to overcome the In distortion of the box walls by making them of' very heavy section. On the other hand, it. has been proposed to make covers of light sheet metal and provide a structural frame for supporting them. It is the object of my invention to im- 15 prove on such constructions of annealing covers as have been known heretofore and to provide a cover which is characterized by resistance to sagging and warping to a greater extent than previous designs ofcovers.

In a preferred form, my invention comprises an open bottomed box or cover having side and end walls and a. top composed of a plurality of arched sections extending across the width of the cover. Transverse ribs or beams are disposed 5 between adjacent sections to support them' while permitting yielding to allow for expansion and contraction of the sections. The following detailed description of the invention refers to the accompanying drawing illustrating a preferred embodiment. In the drawing:

Fig. 1 is a plan view;

Fig. 2 is a side elevation;

Fig. 3 is a sectional view taken along the plane of line III-III of Fig. 1;

Fig. 4 is a partial longitudinal section taken along the plane 6f line 1VIV of Fig. 1;

Fig. 5 is a detailed view showing one of the transverse ribs partly in section along a central longitudinal plane; and

Fig. 6 is a sectional view taken along the line VI--VI of Fig. 5.

Referring in detail to the drawing, a cover or the like I0 comprises side 'wallsll, end walls I2 and a top 13. The side and end walls preferably have corrugations extending vertically thereof to give them rigidity. The side and end walls are preferably formed of light plate and are welded ing formed from fiat stock by bending. The tops of the ribs are cut down adjacent their ends and covered withtriangular plates I6 welded thereon. The ends of the ribs are welded to the angles l4. Stifiening plates 11 are welded between the spaced sides of the beams I5 and at intervals along the length thereof.

Panels inthe form of arched plate sections 18 are'disposed between adjacent ribs l5 and between the end walls and the ribs nearest them. Special angles H! are welded along the top edges of the end walls to provide abutments for the sections l8 nearest the ends. The sections [8 have corrugations extending in the direction of their curvature and are welded at their edges to the ribs l5 and angles l9.

Lifting loops 20 having rings 2! thereon are welded to the side walls at convenient points.

The cover is constructed, as stated, of relatively light weight plate so that its total weight, even in the larger sizes, is relatively small. The cost of the cover is likewise low because the fabricating operations involve only simple bending and welding. Since all joints are welded, the cover constitutes a thoroughly gas tight enclosure.

Since the span of the arched sections I8 is 2 relatively short, their rise is small so that the total height of the box is only slightly greater than the maximum height of stack with which it may be used. Because of the corrugations formed in the sections 18, expansion or contraction of the ribs introduces little or no stress into the former. At the same time, if the sections it tend to expand or contract in the direction of their curvature, the ribs l5 will yield laterally to the extent necessary to accommodate such expansion or contraction. Similarly, the corrugations in the side and end walls permit expansion and contraction of the angles I4 and [9 without introducing heavy stresses thereinto. Since all parts of the cover are composed of relatively light plate, only small stresses are produced by expansion or contraction even at the joints.

The-arched sections l8 have considerable stifiness for their weight and support no load except their own weight. They are thus characterized by relatively little tendency to sag or collapse 1 even when highly heated. This advantage of the invention and those already mentioned make it particularly desirable for large covers such as are necessary for the annealing of automobile body sheets, for example.

The cover may be composed of ordinary low carbon steel plate or of alloy steels resistant to high temperatures and oxidation. Since the f overall weight of the cover is small, such alloys may be used without greatly increasing the cost.

Although I have illustrated herein but a preferred form of the invention, it will be recognized that changes in the arrangement and construction disclosed may be made without departing from the spirit of the invention or the scope of the appended'claims.

I claim:

1. An open-bottomed cover including a top, and side and end walls composed of metal plate, said top comprising a plurality of curved panels disposed in spaced relation along the length of the cover so as to be convex upwardly, and stifiening 15 ribs between said panels, said ribs being troughshaped in section, disposed with their edges downwardly and extending between the upper edges of said side walls,- the edges of said panels 1 being welded to the edges of said ribs.

2. An open-bottomed cover comprising two sides and two ends of sheet metal having vertical v corrugations, uncorrugated structural members surmounting the corrugated side members and welded thereto, covering the ends of said corrugations, a beam member of inverted V-shape spanning the space between said uncorrugated structural members and supported thereon, and 10 a'plurality of curved, corrugated panels abutting said V-shaped beam member, the edges of the latter cdverlng the ends of the corrugations in said panels, all joints between said parts being welded to form a substantially air-tight annealing is cover. I,

GEORGE M. CROFT. 

